Island



No. 622,554. Patentcd Apr. 4, |899.

J. II. SMITH.

APPARATUS FOR GRAINING METALLIC PLATES FR SURFACE PRINTING.

(Application led Dec. '7, 189B.) (Nn Model.)

INVEIN'TD R1 me Nonms Eriks co, moouwc.. WASI-Immun. D. z;

Nrrn Sra'rns nrnnrr innen JAMES II. SMITH, OF PROVIDENCE, RIIODE ISLAND,

I APPARATUS FOR GRAINING METALLIC PLATES FOR SURFACE PRINTING.

SPECIFICATION forming part of Letters Patent No. 622,554, datedApril 4, 1899.,

Application filed December 7,1898. Serial No. 698,520. (No model.)

To a/ZZ whom t may concern:

Beit known that LJ AMES H. Snirrno'f Providence, county of Providence, State of Rhode Island, have invented an Improvement in Apparatus for Graining Metallic Plates for Surface Printing, of which the following description, in connection with the accompanying drawings, isa specification, like letters on the drawings representing like parts.

In that class of printing which is known as surface printing mechanically-grained plates of zinc and aluminium are now extensively employed instead of lithographie stone; but heretofore it has not been possible by means of the apparatus employed forthe purpose to produce as iine a grain upon the metallic plates as can be produced upon a ne lithographie stone. Hence the metallic plates have been 'employed only for the eoarser grades of work.

It is the object of my present invention to provide means by which to produce upon metallic plates a grain which in its printing qualities is equal to that of the best lithographie stone.

In the accompanying drawings, taken in connection with the following description, I have disclosed my invention in the best form now known to me, although I desire it to be understood that I do not thereby restrict my invention to such particular form.

In the drawings, Figure l is a top or plan view of a machine containing my invention; Fig. 2, a vertical section taken in the line 2 2 of Fig. l; and Fig. 3 represents in full size a side and edge view of one of the pieces of cloth or felt that are or may be employed as a graining device to produce, through a suitable graining agent, the required surface on the printing-plate.

Referring to the drawings, A represents one form of what I shall hereinafter designate as a plate-support, upon or to which the plate B, of zinc, aluminium, or other suitable material to be grained, is secured in suitable manner, as by tacks; (Not shown.) This plate-support A may conveniently constitute, in whole or in part, the bottom of a suitable receptacle, the sides of which are indicated at a c. y

' The graining agent I?, preferably a suitable grade of sand, is placed upon the surface of the plate to be grained and within the receptacle, the Walls of the latter permitting the introduction of sufficient liquid c, as water, to obtain the best results from the action of the graining agent. To distribute the sand and at the same time cause the same properly to act upon the surface to be grained, I provide one or more graining devices CZ, herein shown as of felt, which when the plate B is agitated is or are shaken about on the surface of the plate, causing the graining agent or sand to abrade or grain the said surface uniformly and smoothly throughout. This agitation of the plate and graining devices one with reference to the other maybe obtained in various ways. In the present instance of my invention I obtain it by means of two cranks O O, the crank-pins e e of which are connected to -the plate-support A, so that rotation of the crank imparts a rotary or gyrating movement to said plate-support and plate, causing the water, the graining agent, and the graining device or devices to be shifted about by inertia on the surface of the plate in various, also circular, directions, so as thoroughly and completely to grain every portion ofthe surface of the plate B. The cranks O O have their vertical shafts or journals iitted with bevel-gears f g', which are driven by corresponding gears f g on the drivingshaft D.

The plate-support or receptacle is shown as mounted at its four corners upon antifrictionballs t, thus providing for easy motion of the parts.

To balance the parts and enable the platesupport to be gyrated ata high rate of speed, I have counterbalanced the cranks O Cwith Weights h 7L, so that no vibration Whatever is felt of the floor upon which the machine is mounted.

Prior to my invention graining-machines have been provided wherein the graining devices have been spherical balls or marbles of stone, glass, or other hard refractory material, and while the coarser grades of graining have been successfully obtained by the use of such devices yet the action has been so harsh that it has been impossible to obtain a grained surface suitable for the irst surface printing.

While it has heretofore been supposed that onlyhard and refractory materials could be IOO heretofore employed, and at the same time by y reason of its yielding nature my novel graining device acts between or around the finer particles of the graining agent or otherwise to reduce the harshness of the graining actio'n and leave the grained surface ner'than l I have found felt, such as shown in Fig. 3, to be excellently adapted for this purpose because of its soft@ yielding surface,which produces a mild grainwould otherwise be possible.

ing action coupled with an apparent wiping,

coarseness of the grain.

practice produce the best results yet known to me.

In place of the feltI may employ any other material that furnishes a more or less yielding active surface-such as cloth, Wood, sawg dust, excelsior, rubber, leather, cork, pulp," &c.-and the graining devices themselves may be of desired size and shape.

but the number may be'varied.

required surface of the plate.

the metallic surface to be grained.

posited on the plate is or are likewise endless,

and the endless or circular paths'of movement ,of the graining device or devices on the plate V will interlace one with another so closely as to produce an absolutely uniform graining action upon the plate, free from pronounced streaks in one direction as compared with another, as would result if there was a pronounced movement of the support or the graining device or devices in any one direction as colnpared with others-for example, as when the support is reciprocated forward and back in a straight line, in which case the graining action is not a's uniform as when the movement is such as-to be substantially uniform in all directions without prominence in any one.

The machine shown illustrates the simplest means for producing such a uniform graining action, although it is not necessarily the only means, noris myinvention limited specifically to this means.

Having described `my invention, What I claim, and desire to secure by Letters Patent, 1s-

l. In a graining-machine, the combination with la support for a plate to be grained, of a graining agent, and one or more graining dewhich still further reduces the tendency to? By absorbing the water and holding to a greater or less extent 1 the particles of the graining agent it furnishes the required Weight and surface, which in vices loosely arranged with reference to said plate-support and the plate thereon, each of said graining devices having a yielding surface, means to impart to said graining devices and to said plate-support and plate a relative body movement adapted in the presence of the graining agent to produce the required grained surface upon the plate, and means surrounding said plate to retain the graining devices and graining agent thereupon.

2. In a graining-machine, the combination with a support for a plate, of a graining agent 4 Yand one or more felt graining` devices loosely I find the best results to be obtained from a large number of relatively small pieces or devices massed upon the surface to be grained; i In fact, eX- l cellent results may be obtained by means of| a single layer, sheet, or device presenting the p arranged with reference to said plate-support and plate, and having each a yielding surface, and means to impart thereto and to said platesupport and plate a relative body motion adapted in the presence of a graining agent to produce the required surface, land means g surrounding said plate to retain the graining In the present instance of my invention the relative movement between the graining devices and the metallic plate is obtained byf' agitation of the plate, causing thevgraining@ devices and the graining agent or agents by their inertia to be shifted about and upon the surface of the metal; but myinvention comprehends any suitable shape or construction of receptacle, ifa receptacle be employed, and any desired means for causing the shifting of the graining device or devices about and upon devices and graining agent thereupon.

3. In a graining-machine, a support for the plate to be grained, a graining agent, one or more graining devices adapted to be arranged loosely upon the said plate, means to impart to said graining device or devices and to said plate-support, at all points thereof, a uniform relative motion in an endless path to cause said graining device or devices to grain the plate surface uniformly and without pronounced streaks in any one direction as compared with another and means surrounding In the machine herein shown and described the agitation or movement imparted to the plate-support A is in an endless path, shown; as circular, so that the movement or move-y ments of the graining device or devices de-,I

said plate to retain the said graining devices and graining agent thereupon.

In testimony whereof I have signed my name to this specification in the presence of two lsubscribing witnesses.

JAMES H. SMITH.

Witnesses:

MARCUS M. BURDICK, IDA F. DRowN. 

